This invention generally relates to a method and apparatus for identifying sequential content stored on a storage medium. Specifically, the present invention pertains to utilizing stored timing information and/or frame information to identify content and/or a given storage medium on which the content is stored.
A problem exists in the usage of storage mediums for storing content that is retrieved in a sequential manner such as time sequential content. With large storage mediums, such as a digital video recording device, the storage medium may contain numerous individual content portions that can only be identified by reviewing each individual content portion. In smaller storage mediums, such as analog vertical-helical scanning (VHS) tapes, generally video tapes, the video tapes may only contain a relatively small number of individual content portions. However, a given user typically utilizes multiple video tapes and therefore the problem is further compounded in that not only must a particular content portion be identified, but a particular video tape on which the content portion is stored must also be identified.
In the prior art, there is no system for automatically identifying a given content portion or a given storage medium. For commercially recorded mediums, the manufacturer typically affixes a label to the storage medium. The label may contain identifying information such as the storage medium content, total content runtime, content production information, etc. However, over time these labels may become separated from the storage medium, such as the video tape cassette, thereby requiring a user to play the video tape and thereby visually identify the content. For user recorded content, the user is required to affix a blank label to the storage medium and note content identifying information on the blank label. Additionally, a user may note content identifying information on a storage medium carton for the purposes of identifying the content on the storage medium. This is a process that oftentimes is neglected by the user and results in storage medium or multiple storage mediums that contain recorded content that is not identifiable without visually reviewing the content on a reviewing device, such as a television, audio tape player, computer monitor, etc.
Even in a case wherein the storage medium or the storage medium carton contains information identifying the content of the storage medium, there is no ready way to identify a current viewing position of the content without starting the content at a beginning position. In the case of a digital storage medium, some positional information, such as frame data, etc., may be available for prerecorded content, but typically is not available for user recorded content. After starting the content portion from the beginning, such as by rewinding a video tape, a counter may be reset to identify the time sequential beginning of the storage medium. For example, for video tape, the video tape may be rewound to the beginning.
Regardless of the type of storage medium, resetting the counter at the content initial position causes the counter to contain storage medium time positional information that corresponds to the time sequential beginning of the content portion and/or the storage medium. Thereafter, when the content portion is played in a time sequential manner, fast-forwarded, etc., the counter will contain content time positional information that will correspond to the current time position of the content. However, if the current storage medium is replaced with a new storage medium, the above procedure must be repeated for the new storage medium so that the counter will contain the proper time positional information for the content contained on the new storage medium.
Time positional information is particularly important in a case wherein the storage medium contains more than one recorded program. In this case, when the user wishes to review content that does not start at a known place on the storage medium, the user may ensure that the storage medium begins at the initial position before the user resets the counter to reflect the storage medium initial position. For example, the user may rewind the video tape, etc., before resetting the video tape counter. Alternatively, the user may review a content portion at a current position, make a rough determination of the current sequential position of the reviewed content, and then reposition the sequential position of the content to find a desired content position. As a third alternative, the user may review the content at a normal or accelerated reviewing speed while sequentially repositioning the content to find the desired content position.
All of the above procedures are particularly cumbersome for a user. In some consumer equipment, some positional information may be available from the storage medium. For example, in some video cassette recorders (VCRs), indexing information can be recorded directly on a control track of a video tape. In the Video Indexing Search System (VISS), an indexing mark is placed on the control track of the video tape each time recording begins. The recorded index marks are not distinguishable from each other. In this way, if a user wishes to view the third recorded program on the video tape, the user can enter a fast forward or rewind mode to go a particular number of index marks forward or backward. However, this system has the disadvantage in that the user must still first identify where the video tape is presently positioned to determine how many index marks there are between the current position and the desired position on the video tape. In addition, this system only enables a user to proceed to the beginning portion of a content portion or to a content position wherein the user specified an additional index mark at the time of recording. This system does not enable a user to identify the content of the video tape or the current video tape position in the time domain.
In an alternate known system, Video Address Search System (VASS) pulses are stored on the control track of the video tape. The VASS pulses have an advantage over the VISS pulses in that the VASS pulses are distinct from each other. Accordingly, a user can fast forward or rewind to a given VASS pulse (e.g., go to VASS pulse three) without having to determine where the video tape currently resides. However, this system still does not help a user identify the video tape or the current video tape position in the time domain. In fact, both the VISS and the VASS pulses are more akin to a bookmarking system that provides no information on the recorded content.
In yet another known system, a time code is recorded on the control track of the video tape. This time code can be used for identifying the current position of the video tape in the time domain but does not help a user identify content stored on the video tape. For a digital storage medium, time domain positional information may be available from the storage medium yet again this does not help a user identify content stored on the storage medium.
In other known systems, keyframes are extracted from video sequences to facilitate video editing, storage, retrieval, commercial skipping, etc. For example, in U.S. patent application Ser. Nos. 08/867,140, 08/867,145, 09/220,277, and 09/123,444, to Dimitrova et. al., incorporated herein by reference, key frames are identified through the use of techniques such as cut detection, static scene detection, similar frame detection, black frame detection, text detection, commercial detection, etc. Extracted keyframes from a video sequence may help a user to identify the corresponding video sequence but do not help automatically identify the content or the storage mediums current reviewing position in the time domain.
Accordingly, it is an object of the present invention to overcome the disadvantages of the prior art.
It is a further object of the present invention to provide a method of facilitating the use and operation of a storage medium.
These and other objects of the present invention are achieved by a system that utilizes a determined time between characteristics from content for subsequently identifying the content and/or the corresponding content review position in the time domain. The system utilizes a database of previously stored times between characteristics from known content for matching to the determined time between characteristics from the content. The characteristics may correspond to video tape indexing data, keyframe data, audio characteristics, text occurrences, and/or other known characteristics from the content. When a match is found between the determined time between characteristics and the stored times between characteristics, the system identifies the content. In addition, if corresponding time domain data is stored in the database, the system identifies the current content review position in the time domain.
In accordance with the present invention, when the time between characteristics from the content does not match any of the times stored in the database, the system stores the current time between characteristics and corresponding content identifying information in the database for identifying the content at some subsequent time.
The characteristics from the content may be all one type of characteristic, such as index marks, keyframes, text occurrences, scene transitions, a given audio characteristic, etc. In addition, the characteristics may be any combination of the above and other known characteristic types.